Vacuum capping machine



Sept. 14, 1937. R. J. STEWART ET AL 2,092,860

VACUUM CAPPING MACHINE Filed May 14; 1935 3 Sheets-Sheet 2 7'0 View/MiSept. 14, 1937. R. J. STEWART ET AL 2,092,860

5 Sheets-Sheet 5 .JZWAV/? y a a ZZZ? VACUUM CAPPING MACHINE Filed May14, 1955 Patented Sept. 14, 1937 UNITED STATES vacuum carrme MACHINERobert J. Stewart and John E. Erhardt, Baltimore, MIL, assignors toCrown Cork & Seal Company, Inc., Baltimore, MIL, a corporation of NewYork Application Mas 14, 1935, Serial No. 21,423

25 Claims.

This invention relates to an apparatus for capping receptacles under avacuum so that the contents of the receptacle are subjected to thevacuum at the time that the caps are applied. The apparatus of thepresent invention, however, may be used to cap receptacles underatmospheric air pressure, since the vacuum producing means can readilybe rendered ineffective if desired. Moreover, the apparatus is capableof use as a simple vacuumizing apparatus because the cap applying meanscan be rendered inoperative, at will. I r

Although the apparatus of the present invenr tion may be used to applymany different types of closures to a wide variety of receptacles, it isparticularly adapted for use with closures of the type shown in theapplication I of Robert J. Stewart, Serial No. 746,457, filed October 1,1934.

It is an object of the present invention to pro- 20 vide a machine forthe purposes described which is simple and compact and inexpensive tobuild,

Preferably, the machine is portable, so that it may be moved from placeto place in the packing plant where it is being employed.

It is a further object of the invention to provide a machine having anovel and eflicient method of operation. Preferably, the cycle ofoperation will be performed automatically after a particular batch ofreceptacles has been placed 30 in the machine and the operationinitiated.

It is a further object of the invention to provide electrical controlmeans whereby the machine may be used, selectively, to cap thereceptacles at atmospheric pressure; to subject the 35 receptacles tothe influence of a vacuum without the application of positive cappingforce; or to cap the receptacles by positive capping applying I forcewhile subjected to a vacuum.

The machine of the present invention is pref- 40 erably so constructedthat it may be connected to a suitable vacuum source and to a source ofelectric energy to perform the desired operations upon the receptacles.In the preferred embodiment of the invention described below, hydraulicforce is used to supply the capping pressure, and an electric motor-pumpcircuit is employed to create the hydraulic pressure. When the machineis used both to vacuumize and to cap receptacles, initiation of thehydraulic capping pressure is preferably controlled by a predetermineddegree of vacuum in the capping chamber. Furthermore, the cap applyingforceis terminated when the capping operation has been completed bymeans controlled by the hydraulic pres- 55 sure itself, the said meansserving to cutoff the pump motor, relieve the hydraulic force, and,break the vacuum in the capping chamber. Also, means for adjusting themaximum vacuum which can be created in the 'capping chamber areprovided, together with means for adjusting the degree of vacuumeffective to initiate application of the cap applying force. Moreover,adjustablemeans for controlling the amount of hydraulic capping forcewhich can be applied to the receptacles are provided.

It is a further object of the invention to provide a novel combinationof electrical control elements connected in a novel electric circuitwith a novel combination of mechanical and hydraulic elements to providea plurality of entirely new selective cycles of operation. I It is afurther object of the invention to provide a machine which is adjustablefor different sizes of receptacles.

It is a further object of the invention to provide novel closing meansfor the vacuum capping chamber in the'form of specially constructed,pivotally mounted doors. v

Other and further objects and advantages of the machine will be apparentto one skilled in the art after a consideration of the specificembodiment of the invention illustrated in the accompanyingdrawings anddescribed below.

In the drawings:

Figurel is a vertical sectional view of the machine looking toward therear.

Figure 2 is a side elevation of the machine partly in section, takenfrom the left of Figure 1.

Figure 3 is a horizontalsectional view taken on line 3-3 of Fi ure 2. p

Figure 4 is an enlarged sectional view of a detail of the hydraulicpressure chamber and relief valve.

Figure 5 is an enlarged sectional detail of the vacuum relief valve.

Figure 6 is a circuit diagram of the machine showing the novelcombination of elements employed, together with the vacuum lines, theoil pressure circuit, and the electrical control circuits.

The machine of the present invention preferablyv comprises a basecasting it provided with wheels or casters ll, so that the machine canbe moved from place to place, as desired. Projecting upwardly from thebase is a cylindrical post l2, which may be integral therewith or aseparate piece appropriately secured in place. Within the cylinder l2there is an elongated piston I3 having a head l4 provided with anappropriate packing IS. The upper end of thepiston The upper end of thecylinder 12 is flanged-outwardly as at It and is provided with adepressed chamber I9 having a drain plug 2' to permit drainage of waterused for washing the chamber. The flanged portion It serves as a supportfor the vacuum chamber indicated generally at 2|. The chamber comprisesupstanding side walls 22, 23, connected together by a top wall 24.

These walls may conveniently be in the form of an inverted U-shapedcasting, or they may be separate pieces bolted or otherwise securedtogether. The front and rear ends of the chamber are thus normally open,and specially constructed doors .25, 28 are provided for the purpose ofclosing these open ends.

Referring to Figure 2, the front end door 25 is shown, in the fulllineposltion, as being swung upwardly to closed position. The upper edgeof the door 25 is provided with a horizontally and forwardly projectingflange 25' or the like, adapted to act as a bridge spanning the spacebetween the infeed conveyor X and the chamber when the door is open.Furthermore, this element serves as a weight tending to urge the doorsto open position. The side edge of the door 25 at its upper end isprovided with an appropriate stud 21.journal1ed in the upper end of adiagonal cross lever 28. This lever is pivoted to the side wall of thechamber at 29, and its other end is pivotally connected to stud 30,formed on the lower side edge of the rear door 26. As shown in Figures 1and 3, the opposite side edges of the doors are provided with a similarcross lever 28'.

In addition to the two cross levers gonnecting the two doors together,each door is provided with a pair of guide links, the links of each pairbeing disposed on opposite sides of the chamber. Door 25 is providedwith link 3| (Fig. 2) connected to stud 32 at one end and to a fixedstud 33 at the other. A similar guide link for the door 25 is disposedat the opposite side of the machine, as shown at 3|, Fig. 1. The door 26is connected to the chamber by guide links 34, 34', plvotally connectedto studs 35, 36.

An adjustably mounted presser head is disposed within the chamber 2i.Although many alternative means for mounting the head at variousdiflerent heights in the chamber will occur to one skilled in the art,the means disclosed herein has been found to be particularlysatisfactory. Each side wall of the chamber is provided on its innersurface with a pair of racks 31, 38, 39, 43. The racks have a pluralityof vertically spaced slots 4| formed therein. The presser head 42 haslaterally projecting side edges 43 which fit into any desired set ofslots. The presser head is removable and. insertable through the opendoors, so that it may be taken from one position and inserted into the:chamber at a different position to accommodate different sizes of Jars.

It should be noted that the presser head is provided with a smooth,plain, uninterrupted lower face 42'. Also, the receptacle carrying trayl1 preferably has a plain uninterrupted receptacle supporting surface inthe form of a rubber or other resilient pad l'l'. Thus, the necessityfor positioning the receptacles in accurate, predetermined position isavoided. Moreover, the rubber pad compensates for the usual, slightvariations 1n the height of the Jars, and prevents breakage of the sameduring capping.

. The base ll at a point oil-set from the upstanding cylinder i2 isformed with an enlarged opening 45 which serves as a convenient space toreceive an underslung, flanged oil reservoir 49. The flange 41 thereofis positioned over the margins of the opening ll to support the parts.The upper side of the reservoir 46 is closed by a plate 48 whichservesas a supporting base for the operat-. ing mechanism, now to bedescribed.

An electric motor 49 is connected in conventional manner to a hydraulicforce pump II, which may conveniently be of the meshing gear, expansiblechamber type. The pump 50 is connected to a suitable intake conduit 5|extending through the plate 43 down into the reservoir, to a point nearthe bottom thereof, as shown in Figure 2. The high pressure dischargeside of the pump is connected through a special pipe fitting 52 to apressure chamber 53 by means of conduit 64. A conduit 55 leads from thehigh pressure chamber 54 to the space 56 below the piston head M. Thisspace may be defined by a cylinder head 51 appropriately bolted inplace.

Another branch of the Y-iltting 52 carries a pressure responsiveelectric switch 58, adapted to make and break an electric circuit uponpredetermined pressure changes in the hydraulic pressure line, as willbeexplained below in connection with the operation of the machine. Thisswitch includes adjustable means to render it effective .to make andbreak the circuit at different pressures, as desired by the operator. Anoil pressure gauge 59 is also connected to the fitting 52.

The high pressure chamber 53 is provided with a pressure relief valveindicated generally at 60 (Figs. 1 and 2). The valve is controlled by avertically reciprocable stem 6| having a spring 62 enclosed within thesleeve 62a, normally tending to urge the valve downwardly to closedposition. The valve (Fig. 4) comprises a head 60a adapted to, closedownwardly 0n the seat 602). .he rod 6| extc as upwardly through a guidesleeve'62b threaded in sleeve 62a, and acting as an adjustable abutmentfor the upper end of spring 62. The upper end of the valve rod 6|extends between the bifurcated end 83a of a lever 63, pivoted at 63b toan upwardly extending bracket 62c supported by sleeve 62a. Rod 6|, abovethe lever 63, is provided with a downwardly facing abutment, such as anut Gla, engaging the upper surface of the lever.

Referring to Figure 1, the interior of the vacuum chamber 2| is incommunication with a conduit 64 by means of an appropriate connectionextending through a side wall thereof. The conduit 64 is connected atits lower end with a valve housing 65, and the latter is provided with2. laterally disposed port 66, (Fig. 2) which, in turn, is connected to,conduit 61 terminating in a fitting 68 adapted to be connected to asuitable source of vacuum. The source may be a constantly orintermittently running vacuum pump, or a pump in circuit with arelatively large vacuum tank.

Disposed within the valve housing 65 is a slidable balanced vacuumcontrol valve 69 having heads 10, 1| and a stem 12. Surrounding the stem12 is a compression spring 12a, tending to raise the valve 69, the lever63 and the oil pressure relief valve 60. The strength of spring 12a, andthe mechanical advantage resulting from its point of operativeconnection with lever 63 are sufiicient to overcome the downward forceexerted by spring 62, so that, in the normal position the parts areraised upwardly from the position shown in Figure 1. When the valve 62is inthe position shown in Figure 1, the interior of the chamber 2| willbe in direct communication with the source of vacuum connected tothefltting 68. When the valve is in the upper position so that the headII is disposed between the orifice at the end of conduit 64 and theorifice 66, the interior of the vacuum chamber will be in directcommunication with the atmosphere through the lower open end of valvehousing 65.

Connected to the vacuum conduit 64 is a branch pipe 64a having a manualvalve 64b leading to an adjustable vacuum switch 640, adapted to play animportant part in the cycle of operation of the pump driving motor, aswill be described below.

At atmospheric pressures this electric switch is open, but is closed bythe creation of a predetermined, adjustable vacuum in the chamber 2|.

As a means for controlling the operation of the vacuum valve 69 and thepressure relief valve 69, there may be provided a solenoid 15 connectedto the lever 63. The lower end of the valve stem 12 is connected to thefree end of the lever, and, as previously noted, the valve stem iii ofvalve 60 has a unidirectional, one-way connection with that lever.

The operating parts supported by the plate 48 are preferably enclosed bya housing 11 bolted or otherwise secured to the base. The pressureresponsive and vacuum responsive switches and the pressure gauge arepositioned somewhat above the other parts, and are enclosed by. areadily removable hood T8, to permit inspection and adjustment of theparts.

As a means for controlling the degree of vacuum to be created in thevacuum chamber, a spring-pressed vacuum relief valve and a vacuum gaugeare provided. The vacuum relief valve may be of any approvedconstruction, but

the one disclosed in Figure 5 is preferred. A spring 81 serves to urgethe valve stem 82 and valve body 83 upwardly to closed position. Thetension of the spring may be varied by changing the position of the nut84, so that the valve will open under varying degrees of pressuredifferential, to permit the vacuum to be relieved automatically atdifferent degrees of vacuum.

The operation of the machine, and the combination of electrical controldevices, and the circuit which effects that operation can best beexplained by a reference to the circuit diagram of Figure 6.

The two wires of a conventional power line are represented by- 9001. andb, respectively. A magnetic relay switch 9| is provided with two out-putterminals 92, 93, and a plurality of control switches 94, 95, 96. Theswitch 96 is known in the art as a limit switch, and includes an arm 96a(Fig. 1) adapted to be controlled by one of the links or levers pivotedon the side of the chamber so that the switch will be momentarily movedto circuit closing position as the doors are closed. The switch isconnected in parallel with the vacuum switch 640, for purposes describedbelow. The switch 94 is a manual control switch to facilitate startingand stopping of the machine in certain instances. The contacts 94a arenormally closed, but may be opened temporarily by pressing a stop?button associated with the switch. A circuit from contact 94b to 94a.may be temporarily completed by pressing a start button associated withthe switch 94, for purposes to be described below.

In the operation of the machine for vacuumizing and capping thereceptacleathe switch 94 is in normal position with the circuit closedthrough contacts 94a. When the doors are closed, the

switch 96 will be temporarily closed, and the current will flow from theline 9011 through line 97, through the switch 96, thence through switch94 and back to the double pole magnetic. relay 9| by line 96. This willenergize the electro-ma'gnet 9|a of the relay and throw the switch toclosed position, to permit the current to flow from the terminals 92,93. a I 4 The electro-magnet 9|a is kept energized and the relay heldclosed by a flow of current from the terminal 93 through wire 93a,through thenormally closed oil pressure switch 56, wire 931), normallyclosed contacts 94a of a switch 94, wire 96, electro-magnet-9la. to line9%. Thus, as long as the oil pressure switch and the manual controlswitch remain in the normal closed position the electro-magnet 9la. ofthe magnetic relay will remain energized and the relay switch closed.

The current flows in one circuit from contact 93 of the magnetic relaydirectly to solenoid"- through lines 93a|09. From the solenoid, thecurrent returns to the contact 92 of the relay by means of lines"ll-92a. Thus, the solenoid 15 will be energized, the vacuum controlvalve 69 will be shifted to vacuumize the chamber, and the oil pressurerelief valve 60 will be closed.

As soon as the vacuum in the chamber has reached a predetermined desiredpoint, the vacuum switch 640 will be closed, and a second circuit willbe completed. Current will flow from the contact 93, through the lines93a-I90, through vacuum switch 640, line I02 and thence to motor 49.From the motor the current will flow through line IM to line 92a andback to the contact 92 of the magnetic relay. As a result ofthis-circuit, the motor 49 will drive the pump 50 and raise the pistonl9 to cap the receptacles. When a predetermined capping pressure hasbeen created, the oil pressure switch 58 will be actuated to break thecontrol circuit for the electro-magnet 9|a of the relay 9|, whereuponthe relay will open and both of the circuits mentioned above will bebroken. Thereupon, the motor 49 will be stopped and the solenoid I5de-energized, which will result in shifting the valve 69 to vacuumbreaking position and shifting the oil pressure relief valve to reliefposi- 1 tion. Thereupon the piston I; will descend and the doors 25, 26will swing to open position under the influence of gravity, when the airpressure inside of the chamber equals atmospheric pressure. removed anda new trayful put into the machine and the doors again closed, theswitch 96 will again close the relay control circuit, and the cycle ofoperation will be repeated.

Whenthe machine is to be used for applying caps at atmospheric pressure,the manual vacuum valve 13 is closed so that valve 69 and the vacuumcontrol switch are ineffective. Theswitch 95 which is connected inparallel-with vacuum switch 64c is closed, thus shunting out the openvacuum switch. After a tray of receptacles to be capped has been placedin the chambers, the doors are left open, and the start button of manualswitch 94 is pressed, temporarily making a contact between elements 94ato 942; of that switch. Current then fiows'through the relay controlcircuit from line 90d, through. line 91, contacts 94b- 94a of switch 94,'and from the latter through line 99 to magnet 9la of the magnet relay9|, to close the same. Current After the capped receptacles have beenflows from terminal 99 through the oil pressure switch 58 and back tothe magnet No, as previously described to hold the relay closed. Anothercircuit is established from terminal 93 through line I90 and solenoid 15back to terminal 92 to close the oil pressure relief valve.Simultaneous- 1y, current flows from contact 93 through line I90, line9541, switch 95, line 95b, line )2, to motor 49, and thence through lineIfll, back to contact 92. After a predetermined capping pressure hasbeen created, and the caps have been applied thereby, oil pressureswitch 59 breaks the relay hold circuit, de-energizes the magnet 9laand. opens relay 9|. Thereupon, the motor is stopped, and the solenoidI5 is de-energized, permitting the oil pressure relief valve to open,which allows the piston l3 to descend. When the machine is to be usedfor vacuumizing only, the motor and oil pump must be renderedinoperative. The hand valve 64b between the a vacuum control valve 69and the vacuum switch 54c is closed, to render that switch inoperative.Furthermore, the switch 95 which, in the mode of operation describedimmediately above serves to shunt out the vacuum switch, is also open,whereby no current can flow to the motor 49. It must be remembered thatthe motor is always in series either with the vacuum switch 640 or themanual switch 95. Therefore, if both of these switches are open, themotor cannot operate. When the doors are closed, the relay controlcurrent will flow from line 90a through line 91, limit switch 96, thencethrough contacts 94a of switch 94 and conduit 98 back through the relaymagnet 9|a to line 99b. The relay hold circuit will be the same asdescribed above. Current will flow from terminal 93 through solenoid 15,and back to contact 92 as previously described. The solenoid will shiftthe vacuum valve to vacuumizing position, andQafter a predetermineddegree of vacuum has been created, as indicated by vacuum gauge 85, theoperator will press the stop button on switch 94 which will break therelay hold circuit by interrupting the flow of current between contacts94a94a. This will cause the magnetic relay to open, and the solenoid 15will be de-energized, and the valve 69 shifted to vacuum breakingposition, where upon the doors may be opened and the jars removed.

The use of the machine as a vacuumizer, and with the capping meansrendered inoperative is advantageous when certain types of receptaclesand caps are being operated upon, notably Mason jars with the presentwell known two-piece Mason cap.

Although the circuit and the combination of electrical control elementshave been described in considerable detail above, in connection with themethod of operation of the machine, it must be understood that wecontemplate many changes in the relation of parts and in the particularcombination of elements disclosed. For instance, it is entirely feasibleto use automatic means to eliminate the manual control of switch 94 whenthe machine is being used for vacuumization alone. Asupplemental vacuumswitch could readily be used to break the relay control circuit after apredetermined vacuum has been created in the chamber, to terminate thevacuumizing operation when the machine is used for that purpose alone.Other and further modifications and changes will readily occur to oneskilled in the art, and all such modifications as come within the scopeof the appended claims or their equivalents are to be considered asbeing within the present invention.

We claim:v

1. An apparatus for capping receptacles under a partial vacuumcomprising a chamber adapted to receive a receptacle and a cap to be.applied thereto, means for exhausting the chamber to create a partialvacuum therein, means for applyingcapping pressure to thecap andreceptacle, means controlled by the capping pressure for breaking thevacuum in the chamber after a predetermined capping pressure has beenapplied to the cap and receptacle, and means for automatically relievingthe capping pressure.

2. An apparatus for capping receptacles under a partial vacuumcomprising a chamber adapted to receive a receptacle and a cap to beapplied thereto, means for exhausting the chamber to create a partialvacuum therein, means for applying capping pressure to the cap andreceptacle, means for limiting the amount of capping pressure applied bythe pressure applying means, means controlled by the capping pressurefor breaking the vacuum in the chamber after a pressure sufilcient tocomplete the capping opera- 9 tion has been applied to the cap andreceptacle,

and means for automatically and simultaneously relieving the cappingpressure.

3. An apparatus for capping receptacles under a partial vacuumcomprising a chamber adapted to receive a---receptacle and a cap, meansfor closing the chamber to atmosphere after the receptacle and cap havebeen placed therein, means for exhausting the chamber to create apartial vacuum therein, an electrical motor, means independent of themeans for exhausting the chamber and actuated by said motor for applyingcapping pressure to the cap and receptacle, means for rendering saidmotor and the capping pressure applying means effective to cap thereceptacles after a predetermined exhaustion of the chamber, meanscontrolled by the capping pressure applying means to break the vacuum inthe chamber after a pressure suilicient to complete the cappingoperation has been applied to the cap and receptacle, and means forautomatically relieving the capping pressure.

4. An apparatus for capping receptacles under a partial vacuumcomprising a chamber adapted to receive a receptacle with a cappositioned loosely thereon, a door for closing the chamber toatmosphere, means within said chamber for supporting the receptacle andcap between relatively movable members, means for exhausting the chamberto create a partial vacuum therein,

means for applying force to one of said members to apply cappingpressure to the cap and receptacle, means controlled by said forceapplying means to break the vacuum after sufllcient pressure has beenapplied to said cap and receptacle by said member to complete thecapping operation, and means for relieving the force applied to saidmember.

sure applying means to break the vacuum in the 1 chamber and relievethe-hydraulic pressure simultaneously after a predetermined cappingpressure has been established.

'7. An apparatus for capping receptacles under a partial vacuumcomprising a chamber adapted to receive a plurality of receptacles, eachof which may have a cap positioned loosely thereon, means for exhaustingthe chamber, valve means adapted, in one position to establishcommunication between the exhausting means and the chamber to create apartialvacuum therein and, in another position, to break the vacuum inthe chamber, means for applying capping pressure to the caps when thevalve means is in the first mentioned position, and means controlled bythe capping pressure applying means to actuate said valve means to aposition to break the vacuum in the chamber after a predeterminedcapping pressure has been applied to the caps.

8. An apparatus for capping receptacles under a partial vacuumcomprising a chamber adapted to receive a plurality of receptacles, eachof which may have a cap positioned looselythereon, means for exhaustingthe chamber, valve means adapted, in one position toestablishcommunication between the exhausting means and the chamber to create apartial vacuum therein, and in another position, to break the vacuum inthe chamber, a piston adapted to apply capping pressure to the cap,means'for applying hydraulic pressure to the piston, and meansresponsive to said hydraulic pressure to actuate said valve means toposition to break the vacuum in the chamber after a predeterminedcapping pressure has been established.

9. An apparatus for capping receptacles under a partial vacuumcomprising a chamber adapted to receive a plurality of receptacles, eachhaving a cap loosely positioned thereon, means including a valvedconduit for exhausting the chamber to create a partial vacuum thereinwhen the valve is in one position and to break the vacuum when the valveis in another position, a piston adapted to apply capping pressure tothe caps, a pump for applying hydraulic pressure to the piston, ahydraulic pressure relief valve, solenoid means operatively connected tosaid two valves, and a pressure responsive switch adapted to be actuatedby said hydraulic pressure to actuate said solenoid means when apredetermined capping pressure has been established, to shift the firstmen- I tioned valve to position to break the vacuum and to shift thesecond valve to position to relieve said hydraulic pressure.

10. An apparatus for capping receptacles under a partial vacuumcomprising a chamber adapted to receive a plurality of receptacles andcaps, a source of vacuum, a conduit leading from said source to saidchamber, an air control valve in said conduit adapted in one position toestablish communication between said source and said chamber and inanother position to open the chamber to atmosphere, hydraulic capapplying means, a source of hydraulic pressure, a liquid conduitextending therebetween, a liquid control valve in said liquid conduitadapted, in one position to relieve the hydraulic pressure. pressureresponsive means in communication with said liquid conduit, and meansassociated with said pressure responsive means to change the position ofboth of said valves after a predetermined cap applying pressure has beenestablished, to open the air control valve to atmosphere andto open theliquid control valve to relieve the hydraulic pressure.

11. A portable apparatus for tacles under a partial vacuum comprising awheeled base including .an upwardly projecting cylinder, a vacuumchamber at the upper end of the cylinder adapted to receive receptaclesto be capped, a pistonin the cylinder terminating upwardly in areceptacle supporting platform discannin recep posed within the chamber,a valved air exhaust conduit communicating with said chamber and adaptedto be connected toa suction source, said a pump in said conduit and arelief valve bypassing the pump from the conduit to the reservoir, andmeans responsive to pressure in the liquid conduit to control theposition of said valves to open the chamber to atmosphere and to open.said relief valve to by-pass position when a predetermined pressure hasbeen established in said cylinder.

12. An apparatus for capping receptacles under a vacuum comprising acapping chamber, hydraulic capping means for receptacles in the chamber,a valve for controlling the flow of air to and from the chamber, anothervalve for controlling the flow of liquid to and from. the hydrauliccapping means and electrical means responsive to hydraulic pressure, inthe capping means to control the positions of said valves to cause aflow of'air to said chamber and a flow of liquid from the capping meansafter a predetermined capping pressure has been established.

13. An apparatus for capping receptacles in a partial vacuum comprisinga vacuum chamber, a hydraulic cap applying device for receptaclespositioned in the chamber, a valve for controlling the flow of air toand from the chamber, another valve for controlling the flow of liquidto and from the hydraulic capping device, solenoid means operativelyconnected to said valves to change the positions of the same, and apressure responsive switch for controlling saidsolenoid means inaccordance with pressure changes in the hydraulic capping device.

14. An apparatus for capping receptacles in a partial vacuum comprisinga vacuum chamber, a hydraulic cap applying device for receptaclespositioned in the chamber, a valve for controlling the flow of air toand from the chamber, another valve for controlling the flow of liquidto and from the hydraulic capping device, a single solenoid operativelyconnected to both of said valves to change the positions of bothsimultaneously, and a pressure responsive switch for controlling saidsolenoid in accordance with pressure changes in the hydraulic cappingdevice.

15. An apparatus for capping receptacles under a vacuum comprising acapping chamber, capping pressure applying means in the chamber, meansfor controlling theflow of air to and from the chamber, means forcontrolling the capping pressure applying means to initiate, terminate,and relieve the capping pressure, said last-mentioned 20 conduit havingan orifice leading to atmosphere means being controlledjointly by thedegree of vacuum in the chamber and the degree of capping pressureappliedby the pressureapplying means.

16. An apparatus for capping receptacles under a vacuum comprising acapping chamber, hydraulic capping means for receptacles in the chamber,valve means for controlling the flow of air to and from the chamber,other valve means for controlling the flow of liquid to and from thehydraulic capping means, and electrical means responsive to apredetermined degree of partial vacuum in the chamber to initiate theapplication of hydraulic pressure to said hydraulic capping means.

17. An apparatus for capping receptacles under a vacuum comprising acapping chamber, hydraulic capping means for receptacles in the chamber,valve means for controlling the flow of air to and from the chamber,other valve means for controlling the flow of liquid to and from thehydraulic capping means, electrical means responsive to a predetermineddegree of partial vacuum in the chamber to initiate the application ofhydraulic pressure to said hydraulic capping means, and electrical meansresponsive to hydraulic pressure in the capping means to control thepositions of said valve means in response to a predetermined hydraulicpressure to cause a flow of air to said chamber to break the vacuumtherein and to cause a flow of liquid from the capping means toterminate and relieve the capping pressure.

18. A vacuum capping apparatus comprising a capping chamber connected toa source of vacuum, valve means for establishing communication betweensaid chamber and said source and between said chamber andatmosphere,-respectively, power driven means for applying cappingpressure to receptacles in the chamber, a switch responsive to vacuum inthe chamber to render said power means effective, and means responsiveto a predetermined degree of capping pressure to shift said valve meansto vacuum breaking position, and to terminate the application oi!capping pressure by rendering said force ineffective.

' 19. An apparatus of the class described comprising means forsupporting a receptacle, means for subjecting the same to a partialvacuum, means for applying a closure to the receptacle, and controlmeans for selectively rendering either of said last-mentionedmeanseffective independent of the other to vacuumize the receptacle or to capthe receptacle, said control means also serving selectively to renderboth of said means eflective simultaneously to vacuumize and cap thereceptacle.

20. An apparatus for treating filled receptacles! comprising means forsubjecting a receptacle to a partial vacuum, means for applying positivecapping pressure to the receptacle, control means to render both of saidmeans simultaneously eiiective, and other control means to render one ofsaid means effective independently of the other.

21. An apparatus for treating filled receptacles comprising a chamber inwhich a receptacle may be positioned, electrically driven means forapplying positive capping pressure to said receptacles, electricallycontrolled valve means for aoeaaao evacuating said chamber, andelectrical control means to render said electrically driven means andsaid electrically controlled valve means eiiective simultaneously tovacuumize and cap the receptacle, or to render either one eflfectiveindependently of the other to cap or to vacuumize the receptacle only. 4

22. An apparatus of the class described comprising a vacuumizing andcapping chamber for receptacles, hydraulic cap applying means for thechamber, an electric motor driven pump for delivering hydraulic forcethereto, a hydraulic pressure responsive electric switch in thehydraulic line adapted to be actuated to open position upon creation ofa predetermined high pressure, valve means for controlling the flow ofair to and from the chamber to establish and relieve a vacuum therein,electro-magnetic means for controlling the position of said valve means,a vacuum responsive electric switch operatively connected to saidchamber and adapted to be actuated to closed position by apredetermined, relatively high degree of vacuum, a source of current andelectric conduits connecting said electro-magnetic meanswith said sourcein one circuit, and connecting said motor, and said vacuum responsiveswitch, in series with said source in another circuit, both of saidcircuits being controlled by said hydraulic pressure responsive switch,whereby said first mentioned circuit will shift the valve means tovacuumize the chamber, and the second circuit will be closed by thevacuum responsive switch after a predetermined vacuum has been createdin the chamber, to start the motor and cap the receptacles, saidhydraulic pressure responsive switch serving to break both of saidcircuits after a predetermined pressure has been established, to shiftthe valve means to relieve the vacuum in the chamber, and to. stop thepump motor.

23. An apparatus for capping receptacles comprising a vacuumizing andcapping chamber, a pair of substantially vertically disposed doors atopposite ends of the chamber for sealing the same from atmosphere, andsupporting means for 'said doors, said supporting means comprising apair of levers pivoted to opposite sides of the chamber, and guide linkspivoted adjacent each lever, each of said levers being pivotallyconnected at one end to an upper portion of one door and at its otherend to a lower portion of the other door, each of said guide linkshaving one end pivoted to said chamber and its other end pivoted to oneof said doors and disposed in parallelism with the adjacent lever,whereby one door may be swung downwardly and the other upwardly to openposition.

24. A device in accordance with claim 23 in which one of said doors isof greater weight than the other, to give the doors a positive swingingtendency in one direction.

25. A device in accordance with claim 23 characterized in that the doorwhich swings downwardly to open position is of greaterweight than theother, whereby the first mentioned door overbalances the second andresults in a tendency to swing the doors to open position.

ROBERT J. STEWART. JOHN E. ERHARDT.

